Label scaling for Google/Yahoo/Bing?

joema

Posted 13 April 2010 - 09:48 AM

joema

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United States

When printing a map from Google/Yahoo/Bing, it is sometimes desirable to scale the label size (i.e, street names) independently from the map features. Currently it seems the label font scaling is hard coded and optimized for screen display, not print display.

Can any of these web mapping programs be fine-tuned by an API or any other means to independently control label size from map feature size at a given zoom level?

Specifically, I want to zoom in and print several streets, and use print scaling to make a fixed-size paper map (say 5 x 7 inches). However this makes the street names too small for optimal readability. Is there any solution to this?

Dennis McClendon

Posted 13 April 2010 - 01:23 PM

I don't think so. I'm pretty sure the streetnames are "baked in the cake," and the online services merely send prerendered tiles to your browser.

There is some Ajax wizardry going on, though, such that turning on and off labels, bike paths, etc., over aerial imagery doesn't appear to retrieve entirely new tiles. So I can't totally rule out the possibility that streetnames could be rendered independently of the background images.

joema

Posted 19 April 2010 - 04:32 PM

joema

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United States

I notice on Google Earth there's a choice of three different label sizes: small, medium and large. That is under tools | options | 3D view, Labels/Icon Size. Google Earth version 5.1.3533.1731. Changing this changes the font size of street names.

Three choices isn't much but it's more than the web map programs have.

With all the emphasis on accessibility (e.g, visually impaired and elderly), I can't believe NONE of the web map sites have label size control. Unlike browsers which allow adjusting of font size for accessibility, the fonts in Google/Yahoo/Bing Maps are fixed size. On my screen this equates to roughly an 8-point font in Microsoft Word. Imagine a word processor or browser which only rendered fonts in 8-point size.

To clarify, your point is NOT that they refuse to expose that functionality, but rather it doesn't exist. IOW all labels are pre-generated at each zoom level and "baked into" the map as a single-layer.

I guess that makes sense: with Google, Yahoo or Bing maps, I've never seen any delay or malfunction which would imply dynamic label generation, either on the client or server side. E.g, labels rendered late, erroneously, label positions changed, etc.

If the labels were dynamically generated, you'd expect that someone, somewhere would eventually see this as a failure mode. Yet the tiles always either appear intact (with labels) or they don't. That implies all the tiles at each zoom level are pre-rendered. IOW just flat, "dumb" raster objects -- labels and map details merged into a single bitmap for each zoom level.

I had an email exchange with Yahoo Maps tech support. They said there is currently no API nor other method of selecting alternate label sizes.

I likewise posted the same question on Google Maps support forum -- no answer, which likely means it can't be done on the current version.